My Skype was running Automatic Updates today, but under the installation it returns the Error: “The installer has encountered an unexpected error installing this package. This may indicate a problem with this package. The error code is 2738.”
This installer error is not just for Skype.

Step 2: Running MSIEXEC with logging options

I started a “Command Promt” and used the command: “cd C:\ProgramData\Skype\{D103C4BA-F905-437A-8049-DB24763BBE36}” to navigate into the folder containing the MSI-file.
Now using the command: “msiexec /i SkypeToolbars.msi /lv log.txt” (msiexec options: /i = Install, /lv = Log + Verbose output).
After clicking away the error message I just wrote “log.txt” in my “Command Promt” to open the log-file. Near the bottom of the log-file I found this line:
DEBUG: Error 2738: Could not access VBScript runtime for custom action

Step 3: DEBUG: Error 2738

After a quick search at Google I found out this error indicates that the VBScript engine is not registered on the computer.

The solution for a Windows Vista or Windows 7 32bit:
- Click Start -> All Programs -> Accessories
- Right click “Command Promt” and click on “Run as administrator”
- Write “cd %windir%\system32” and hit Enter
- Write “regsvr32.exe vbscript.dll” and hit Enter
- You should now get a message that says: “DllRegisterServer in vbscript.dll succeeded.”
- Click “OK”

The solution for a Windows Vista or Windows 7 64bit:
- Click Start -> All Programs -> Accessories
- Right click “Command Promt” and click on “Run as administrator”
- Write “cd %windir%\syswow64” and hit Enter
- Write “regsvr32.exe vbscript.dll” and hit Enter
- You should now get a message that says: “DllRegisterServer in vbscript.dll succeeded.”
- Click “OK”

Step 4: Try again...

Now I tried once more to run “msiexec /i SkypeToolbars.msi /lv log.txt” (I kept the /lv log.txt option to look for changes if the installer would fail again).
If you still get the same Error than continue to step 5.

Step 5: Cleanup registry first, then re-reg

My installation still gave me the same error, so after some more searching and reading on Google I found a solution that explained what I tried before (with the regsvr32.exe) and also an alternative step if that one should fail. The alternative step was to remove the Registry Key pointing to vbscript.dll.

1. The reg delete path could be different. I had to use this one:
reg delete HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{B54F3741-5B07-11CF-A4B0-00AA004A55E8} /f
2. That failed due to permission on the above key; I had take ownership of the key and add full control; I did that via regedt32.
3. Then I was able to:
regsvr32 c:\Windows\System32\vbscript.dll